function isNotEmpty(elem, msg) {
  var str = elem.value;
    var re = /.+/;
    if(!str.match(re)) {
    	if(msg)
        	alert(msg);
        setTimeout("focusElement('" + elem.form.name + "', '" + elem.name + "')", 0);
        return false;
    } else {
        return true;
    }
}
//validates that the entry is a positive or negative number
function isNumber(elem, msg) {
  var str = elem.value;
    var re = /^[-]?\d*\.?\d*$/;
    str = str.toString();
    if (!str.match(re)) {
    	if(msg)
        	alert(msg);
        setTimeout("focusElement('" + elem.form.name + "', '" + elem.name + "')", 0);
        return false;
    }
    return true;
}
// validates that the entry is 16 characters long
function isLen16(elem) {
  var str = elem.value;
    var re = /\b.{16}\b/;
    if (!str.match(re)) {
        alert("Entry does not contain the required 16 characters.");
        setTimeout("focusElement('" + elem.form.name + "', '" + elem.name + "')", 0);
        return false;
    } else {
        return true;
    }
}
// validates that the entry is formatted as an e-mail address
function isEMailAddr(elem, msg) {
  var str = elem.value;
    var re = /^[\w-]+(\.[\w-]+)*@([\w-]+\.)+[a-zA-Z]{2,7}$/;
    if (!str.match(re)) {
    	if(msg)
        	alert(msg);
        setTimeout("focusElement('" + elem.form.name + "', '" + elem.name + "')", 0);
        return false;
    } else {
        return true;
    }
}
// validate that the user made a selection other than default
function isChosen(select) {
    if (select.selectedIndex == 0) {
        alert("Please make a choice from the list.");
        return false;
    } else {
        return true;
    }
}

// validate that the user has checked one of the radio buttons
function isValidRadio(radio) {
    var valid = false;
    for (var i = 0; i < radio.length; i++) {
        if (radio[i].checked) {
            return true;
        }
    }
    alert("Make a choice from the radio buttons.");
    return false;
}

function focusElement(formName, elemName) {
    var elem = document.forms[formName].elements[elemName];
    elem.focus();
    elem.select();
}

// batch validation router
function validateForm(form) {
    if (isNotEmpty(form.name1)) {
        if (isNotEmpty(form.name2)) {
            if (isNotEmpty(form.eMail)) {
                if (isEMailAddr(form.eMail)) {
                    if (isChosen(form.continent)) {
                        if (isValidRadio(form.accept)) {
                            return true;
                        }
                    }
                }
            }
        }
    }
    return false;
}